Bucket chain for trenching machines



1961 R. E. BANSEMER 3,010,334

BUCKET: CHAIN FOR TRENCHING MACHINES Filed May 5, 1958 1611MB 10154? BY Mrk% i United States Patent ()7 3,010,334 BUCKET CHAIN FOR TRENCHING MACHINES Roland E. Bansemer, Newton, Iowa, assignor to Koehring Company, Milwaukee, Wis., a corporation of Wisconsin Filed May 5, 1958, Ser. No. 733,059 1 Claim. (Cl. 74250) The tremendous quantities of material excavated in v trenching and like projects, and the wide variety of materials encountered, require that meticulous attention be paid to the details of the cutting lip or teeth of the excavating buckets in order to obtain an efficient operation.

One of these details involves the selection of the best w cutting angle for the equipment and material concerned. Once this angle has beensdetermined by the selection of the correct buckets and cutting teeth, it then of course is necessary that the buckets and teeth be rigidly held in the desired position as they pass across the face of the material to be excavated. This is particularly so when excavating in rock or the like.

In boom type trenching machines, the problem of maintaining the proper cutting angle for the bucket cutting surfaces is made the more difficult by reason of the flexing of the chains on which the buckets are mounted. The flexing permits considerable tilting movement of the buckets as they move upwardly in cutting engagement with the material being excavated. Various arrangements, such as trackways or closely spaced rollers, or specially designed buckets, have been tried to overcome this difiiculty. However, they have not been entirely satisfactory for a number of reasons, including the reason that they cannot be easily added to existing machines.

Accordingly, a general object of my invention is to provide for boom type trenching machines a bucket angle maintaining means which can be easily and readily added whenever digging conditions require it.

More specifically, an object of my invention is to provide for the excavating buckets of boom type trenching machines a novel chain which will maintain correct cutting angle and which is easily interchangeable with other chains for excavating buckets.

Other objects and the advantages of my invention will hereinafter appear.

Now referring to the accompanying drawing which illustrates the preferred embodiment of my invention, it will be seen that- FIG. 1 is a fragmentary, partly-schematic, view of a boom type trenching machine showing the excavating buckets and their excavating teeth in cutting position and mounted on a chain embodying my invention.

FIG. 2 is a perspective view illustrating the side bar links used in the chain.

FIG. 3 is a perspective view of the center bar spacer link used in my chain.

FIG. 4 is a perspective view of the center bar attachment link used in my chain.

FIG. 5 is a perspective view of the connecting pin used in my chain.

FIG. 6 is a view taken along line 6-6 of FIG. 1, showing only the working face of the bucket carrying chains.

Although only one embodiment of my invention is illustrated in the drawing and is herein discussed, it is to be understood that I do not intend to limit my protection 3,010,334 Patented Nov. 28, 1961 ice thereto, and that the scope of my protection is'to be determined only by my claim as restricted by the prior art.

Referring to FIG. 1, the bucket boom 1 is provided at its lower end with idler sprockets 2 (the second of which is hidden) and at its upper end with driving sprockets (not shown). Flanged rollers 3 are also spaced along the boom. Over the sprockets and rollers run a pair of endless chains 4 to which are attached excavating buckets 5 having teeth 6 for cutting into the end face S of a trench. It should be noted that although the boom '1 and face S are generally parallel the buckets and chains are normally free to move in a sinuous path as they pass over and between the rollers 3. However, in the instant construction, any movement of the buckets inwardly between the rollers under the pressure of its contact with the surface S is resisted by reason of the novel construction of the chains 4 which will now be described in detail.

Generally speaking, my chain is comprised of center bar links which are connected by pairs of side bar links having pin connections therewith. The side bar link 11 is illustrated in FIG. 2. It is of substantially uniform thickness and is provided at each end with pin receiving apertures 12 and keyways 13. Its ends are rounded for clearance purposes.

The center bar spacer link 20, illustrated in FIG. 3, is a spacer link. It is a casting having a body portion 21 of substantially uniform thickness, and a top face or working face 22 which is substantially flat. The body portion 21 may include lightening cavities 21 if desired. Pin receiving apertures 24 are provided at each end of the body portion.

It should be particularly noted that the top face 22 terminates with widened flange portions 23 which respectively extend well rearwardly and forwardly of the pin receiving apertures 24. These flanges are of approximately the same thickness as that of the side bars 11, and the bottom face 23 thereof will just clear the top face of the side bars when pinned thereto as hereinafter described. Preferably, the clearance between the two should be no more than ,4, of an inch.

The center bar attachment link 30, illustrated in FIG. 4, is an attachment link for carrying the excavating buckets 5 or similar cutting attachments. Similarly to spacer link 20 it has overhanging T-shaped end portions 30, 30 which are substantially the same thickness as link 20. The mid-portion 31 of link 30 is of enlarged thickness to accommodate an attachment receiving recess 34 which is in communication with the fiat top or working face 32. Transverse openings 35 are also provided in the mid-portion 31 for accommodation of an attachment securing pin 51 (see FiG. 6).

Side flanges 33 are also provided on attachment link 30, and it is to be noted that they are respectively rearwardly and forwardly of the pin receiving apertures 36. It is also to be noted that the bottom face of the flanges 33 is positioned so as to just clear the top face of a side bar link 20 when secured to link 30 as hereinafter described.

The chain connecting pin 41 is illustrated in FIG. 5. Its length is slightly in excess of the combined thickness of two sidebar links 11 and the end portion of either of links 20 or 30. Its diameter is slightly less than that of apertures 12, 24 and 36 so as to permit insertion therein. Near each end of the pin are slots 42 which provide a key portion 43 and a head portion 44 for cooperation with the key slots 13 of the link 11 in a manner hereinafter explained.

The manner of assembling my novel chains and of using two of them to make up an improved bucket line for a trenching machine is best illustrated in FIG. 6 and may also be seen in FIG. 1.

The number and spacing of spacer links and attachment links will, of course, be determined by the number of buckets and length of chain required.

In FIG. 6 it will be seen that the center bar links 20 'and 30 are connected together by inserting pins 41 in the apertures 24, 36 and then slipping over each of the ends of said pins a side bar link 11. By then placing tension on said side bar links, the neck' or key portion 42 of the .pins will move into the key slots 13 of links 11 to securely'retain said side bar links on the center bar links. An excavating bucket 5 (shown in dotted line) may then be secured to the chains by inserting portions thereof into the attachment link recesses 34 and securing them the rollers 3. Since the ends of'the links 11 are symmetrical about the pivot pin 41 connections there is, of course, no interference with chainbending in the opposite direction.

The obvious advantage of my invention is that improved control of the cutting angle in boom type trenching machines may be obtained by the simple expedient of replacing the conventional bucket chains with my novel chain. Other advantages such as the elimination of the need for additional backing rollers, trackWays and the like will be readily appreciated by those skilled in the art.

I claim:

An excavating bucket carrying chain for use in a trenching machine comprising, in combination, a plurality of cast center links each having substantially fiat, inner,

roller engaging faces and substantially flat, outer faces parallel to said inner faces, and a plurality of pairs of side links coupling said center links by being pivoted at each end on opposite sides of adjacent ones of said center links, said side links having substantially fiat, parallel, inner and outer edge surfaces, said side links being pivoted to said center links so' that, when the links are alined,

7 said inner edge surfaces are in the same approximate plane as said inner faces, said center links being thicker from face-to-face thansaid side link surfacerto-surface dimension so that said center links extend outwardly a uniform distance beyond said] side links, and said outwardly extending portions of said center links having integral flange portions overlying each of the outer edge surfaces of said side links in each of the adjoining pairs of. side links so as to limit inward deflection of said chain.

References Cited in the file of this patent UNITED STATES PATENTS 601,748 Dundas et al. Apr. 5, 1893 1,004,575 Jones Oct. 3, 1911 1,129,517 Powell .'Feb. 23, 1915 1,570,014 Stevens Ian. 19, 1926 1,717,476 Topping June 18, 1929 1,850,364 Vaughn Mar. 22, 1932 2,365,229 Vanderzee Dec. 19, 1944 2,637,917 Klaucke May 12, 1953 2,653,808 Simmons Sept. 29, 1953 FOREIGN PATENTS 137,615 Switzerland Jan. 15, 1930 405,045 Great Britain Feb. 1, 1934 OTHER REFERENCES Moving the Earth (Van Nostrand), published by D. Van Nostrand Co., Inc. (New York), 1955 (FIGS. 14 69, pages 14-47 relied on) 

